Gemara

The (compensation for) Boshes (embarrassment) and Pegam (loss of virginity) is according to the girl and the rapist.

Kesuvos 40a (Mishnah): Embarrassment is evaluated according to the one who embarrassed and the one who was embarrassed;

To evaluate blemish, we appraise how much less one would pay to buy her to be a slave (because she is not a virgin);

(Shmuel's father): We evaluate the difference between what one would pay for a virgin slave and a non-virgin.

He discusses one who has a male slave whom he likes, and he wants to give to him a virgin to marry.

Sanhedrin 2a (Mishnah): Cases of Ones u'Mefateh (rape or enticement of a virgin Na'arah) require three judges.

Bava Kama 15b: We do not collect fines in Bavel. If the victim seized payment, we do not make him return it.

If the victim requested to fix a time to go to Eretz Yisrael to judge the case, we comply. If the damager does not agree, we excommunicate him.

In any case, we excommunicate him until he removes the damager.

84b: We (judges in Chutz la'Aretz) are Sheluchim of ordained judges in Eretz Yisrael to collect only things that are common.

Objection: Boshes and Pegam are common. We should be Sheluchim to collect them!

Answer: Indeed, we are! Rav Papa collected 400 Zuz for Boshes.

Rejection: Rav Papa erred. Rav Nachman taught that we do not collect Boshes in Bavel. We are Sheluchim to collect only common things in which the victim loses money. The victim does not lose money through Boshes, so we are not Sheluchim to judge it.

Rishonim

Rif and Rosh (Kesuvos 14a and 3:7,8): Boshes depends on the one who embarrassed and the one who was embarrassed. We evaluate Pegam as if she was a slave being sold. We evaluate the difference between what one would pay for a virgin slave and a non-virgin, to marry her to his slave whom he likes.

Ran (DH Masnisin Iy): Rashi says that if an average person embarrassed, this is worse than if a lowly or honorable person embarrassed. One pays more for embarrassing an honorable person. It seems that this applies to other matters, but regarding rape and seduction, the more lowly the man, the greater the embarrassment.

Rosh: We evaluate the difference of what one would pay for this woman if she was a virgin or not. Each woman is evaluated based on her worth and her family.

Rif (Bava Kama 30b): The custom of two Yeshivos is that we do not collect fines in Bavel, but we excommunicate until he appeases the victim as Beis Din deems proper, then immediately permit the Cherem, whether or not the victim was appeased.

Rambam (Hilchos Sanhedrin 5:17): The custom of Yeshivos in Chutz la'Aretz is that even though we do not collect fines, we excommunicate until he appeases the victim or goes to Din with him in Eretz Yisrael. Once he gives the proper amount, we permit the Cherem, whether or not the victim was appeased.

Rosh (Bava Kama 8:2): Perhaps this was an enactment of Ge'onim. This is unlike the Gemara. Niduy is the ultimate collection! The Gemara says that we excommunicate until he removes the damager (but not until he pays.)

Rambam (Hilchos Na'arah Besulah 2:4): Embarrassment is evaluated according to the one who embarrassed and the one who was embarrassed. One who embarrasses a distinguished Na'arah from a family of good lineage is unlike one who embarrasses a poor disgraced minor. A distinguished man who embarrasses is unlike a lowly man who embarrasses.

Rambam (5): The judges evaluate his and her standing and evaluate how much money her father and family would have paid to avoid this from happening. He must pay this much.

Rambam (6): We evaluate blemish based on her beauty. We evaluate her like a slave being sold, and calculate the difference between what one would pay for her if she was a virgin or a non-virgin, to marry her to his slave whose benefit he seeks. He pays this amount.

Rosh (3): Should we collect for Ones u'Mefateh in Bavel, lest sinners profit? Rav Tzemach Gaon answered that we do not collect fines in Bavel, but we do not want sinners to profit, and that people will wantonly rape, entice and steal. Therefore, the custom of latter Chachamim is to excommunicate until he appeases the victim with money, or brings friends and verbally appeases him. This is the custom. Rav Shrirah Gaon says that the Gemara says that we excommunicate only until he removes the damager. Latter Chachamim saw a great loss through not collecting fines. They enacted to estimate (how much is proper to give), but we do not tell him the amount. We excommunicate him until he pays close to this amount, or appeases the victim.

Yam Shel Shlomo (8:6 DH ul'Inyan): We excommunicate only until the damager is removed, like the Rosh says. However, I say that the Rif's enactment is proper for wounding and feuds, like the Rosh brought. The Tur (EH 177) rules like Rav Tzemach Gaon, who excommunicates a rapist or enticer until he appeases her father, lest a sinner profit. This is difficult. The fine applies only through witnesses. No one ever heard about Ones u'Mefateh in front of witnesses! We did not enact for something so rare; also, there is no monetary loss. It is proper to excommunicate until he pays pain and Boshes. There is no monetary loss, but the bodily pain and Boshes is more than property damage; it is like monetary loss. The Halachah follows Rava, who is not concerned lest a rapist or enticer profit (Kesuvos 11a). Even though wounding is more common, we do not want a sinner to profit and shame Bnos Yisrael, and empty people should not wantonly have Zenus (extramarital relations). Perhaps Rav Tzemach Gaon meant that we excommunicate only for Boshes and Pegam. Even if all laws of a rapist require three expert judges, it is proper to force him to marry her, even if we must use Nochrim. We force anyone to fulfill a Mitzvas Aseh!

Rosh (15): Rav Shrirah Gaon says that even for verbal embarrassment we put someone in Cherem until he appeases the victim properly according to his prestige.

Question (Tosfos 40b DH Kamah): How can we say that a woman from a prestigious family is blemished only like a Shifchah?

Answer (Tosfos): Indeed, we consider how much a master would pay for a woman of her prestige before and after the Bi'ah. The Gemara discusses a Shifchah only because it is not common to marry a princess to one's slave.

Drishah (EH 177:6 and Bach DH u'Mah she'Chosav Pegam): Normally, a man does not pay a woman to marry himself or his son. Rather, she brings a dowry! Therefore, it discusses a slave. Alternatively, it is a big stringency against the seducer to consider how much one would pay to marry her to his slave. One would not need to pay so much to marry her himself.

Poskim

Shulchan Aruch (EH 177:1): If one seduced a Besulas Yisrael (Rema - from three years until Bagrus), he pays embarrassment, blemish and a fine.

Bach (1): Even if he did not verbally entice her, rather, he requested to had Bi'ah with her and she consented, this is Mefateh, as long as her father did not consent. However, if she prepared herself for this, she is a Kedeshah (harlot), and there is no fine.

Tur: For Boshes, Beis Din estimates how much her father and family would have paid to avoid this.

Taz (2): The Boshes of a lewd girl is smaller than that of a modest Bas Yisrael. Even if we see her act lewdly afterwards, we may assume that she was this way even beforehand. We learn from Bava Kama 90b. A man uncovered a woman's hair, and showed that she uncovered her own hair. He needed to pay because a person may harm himself. If not, he would have been exempt. We do not say that only now she began to act immodestly!

Shulchan Aruch (2): Three judges with Semichah in Eretz Yisrael are needed for Ones u'Mefateh. Nowadays that there are no Semuchim, we excommunicate him until he appeases the other party. Once he gives what is proper to give, we permit him.

Rema: The Tur elaborated about these laws. The Mechaber was brief, for they are not common.

Note: The Gemara said that it is common! Perhaps the Gemara means that Boshes is common, and the Rema says that Ones u'Mefateh is not common (in front of witnesses, or for the man to admit).

Radvaz (1:19, cited in R. Akiva Eiger): If one admits that he raped a girl without witnesses, must he marry her? I did not see Meforshim discuss this. Presumably, we force him to marry her. The Rambam counts paying the fine and marrying her like two separate Mitzvos. This connotes that one does not depend on the other. Marrying her is not a fine. We say 'even if she is lame or has Tzara'as.' This does not mean 'even so, he pays a fine.' Rather, even so he must marry her. Even if you will say that it is a punishment, we do not apply 'one cannot make himself a Rasha.' Further, this is not a fine. It is a monetary obligation to marry her and give to her food and clothing. Why should his admission exempt him?! Chachamim made this Chidush, that one who admits is exempt. It was said only for monetary fines. Also, if such a Chidush were true (that he need not marry her), one of the Poskim would have said so. Granted, a Mefateh may pay a fine and not marry her. If he admitted, he need not marry her, and he is exempt from the fine. A rapist must pay the fine and marry her, so admission exempts only from the fine. Perhaps Rishonim did not discuss this because it is so obvious!

R. Akiva Eiger: Hagahos Semak (182) says that even nowadays we force a rapist to marry the girl if she and her father want. If he is already married, and there is a Cherem not to marry two women, we excommunicate him until he gives to her a dowry to marry someone proper for her. I say that this is only for a Na'arah, for which the verse says "she will be his wife."